#include <cstdio>
#include <vector>
#include <cctype>

#define BUF_SIZE 1 << 17

#define MAXN 100000
#define MAXM 2000000

std::vector <int> g[MAXN + 1], q[MAXN + 1];
int a[MAXM], b[MAXM], ans[MAXM];
int t[MAXN + 1];

int pos = BUF_SIZE, poz = 0;
char buf[BUF_SIZE], fub[BUF_SIZE], c[11];
FILE *fin = fopen("lca.in", "r"), *fout = fopen("lca.out", "w");

inline char nextch() {
    if (pos == BUF_SIZE) fread(buf, BUF_SIZE, 1, fin), pos = 0;
    return buf[pos++];
}

inline int read() {
    char ch;
    while (!isdigit(ch = nextch())) ch = nextch();
    int x = ch - '0';
    while (isdigit(ch = nextch())) x = 10 * x + ch - '0';
    return x;
}

inline void putch(char ch) {
    fub[poz++] = ch;
    if (poz == BUF_SIZE) fwrite(fub, BUF_SIZE, 1, fout), poz = 0;
}

inline void write(int x) {
    int s = 0;
    do { c[++s] = x % 10 + '0'; } while ((x /= 10) > 0);
    for (; s; s--) putch(c[s]);
}

int sef(int x) {
    if (t[x] == x) return x;
    else return t[x] = sef(t[x]);
}

void dfs(int x) {
    t[x] = x;
    for (auto &y : q[x])
        if (a[y] != x && t[a[y]])
            ans[y] = sef(a[y]);
        else if (b[y] != x && t[b[y]])
            ans[y] = sef(b[y]);

    for (auto &y : g[x]) if (t[y] == 0) {
        dfs(y);
        t[sef(y)] = sef(x);
    }
}

int main() {
    int n = read();
    int m = read();

    for (int i = 2; i <= n; i++)
        g[read()].push_back(i);

    for (int i = 0; i < m; i++) {
        a[i] = read();
        b[i] = read();

        if (a[i] == b[i])
            ans[i] = a[i];
        else q[a[i]].push_back(i), q[b[i]].push_back(i);
    }

    dfs(1);

    for (int i = 0; i < m; i++) {
        write(ans[i]);
        putch('\n');
    }

    fwrite(fub, poz, 1, fout);

    fclose(fin);
    fclose(fout);
    return 0;
}